Conduit



Patented July 21, 1936 CONDUIT Roy Sanford, South ndix Brake corporation of Illinois Application March 26, 1930, Serial No.

2 Claims.

This invention relates to conduits and more particularly to flexible conduits and a process for the manufacture thereof.

An object of the invention is to provide a fiexible conduit which may be bent in various positions without injury thereto.

Another object of the invention is to provide a flexible conduit for a cable which will not chafe or otherwise injure the cable.

Another object of the invention is to provide a helical conduit, each convolution of which is so to the adjacent convolution that the conduit may be bentwithout disturbing the continuity of the inner diameter of the cable or causing a separation between the respective convolutions.

A further object of the invention is to provide a helical conduit with a covering wound thereon in an opposite direction with no space between the conduit and the covering, thus preventing compression.

A still further object of the invention is to I provide a flexible conduit formed of a single helically wound element having tapered side walls and cation, and in which:

Figure 1 is a side elevation of a section of a conduit partly broken away with a cable positioned therein embodying the invention;

Figure 2,is a side elevation of a die illustrating the form'in which the strand is drawn;

Figure 3 is a cross sectional view of the strand after drawing;

Figure 4 is a modified form of the invention illustrating a section of a conduit partly broken away and a cable positioned therein;

Figure 5 is an end elevation of the die illustrating the form in which a strand is drawn preparatory to winding; and

Figure 6 is a cross sectional view of the strand drawn and'coiled to form the Referring to the drawing for more specific details of the invention, Ill represents a conduit having a covering II and a." cable I! is positioned in the conduit. The conduit is a helix wound in one direction and the covering is a helix wound in the opposite direction. In practice, the metallic strands from which the conduit and cover- Gompany, South Bend, Ind., assignor-to Bend, Ind., a

438,982 (or. e4 s) ing are wound are both heat treated and wound with no space between the conduitand the covering to prevent compression.

The conduit is wound from a single strand l3.

This strand is first drawn 5 ing the strand is deformed by squaring, as indicated at l9, and rounding the corners and 2|. The form which the strand takes upon winding is largely due to the upsetting of the inner surface and drawing the outer surface. bodiment of the invention,

In the modification, the strand forming the helix I 0 is drawn through a die to incline one of its sides outwardly, as indicated at 22, and to round the corners 23 and 24; Upon winding, the strand takes the form shown in Figure 6, wherein the strand is somewhat flattened and the width at its top portion 26 than at its base 21, hence, the respective convolutions of the helix engage each other at their inner edges and since the engaging portions are rounded, may be bent in various positions within certain limits restricted by the degree of the inclination of the sides 25 without disturbing the continuity of the conduit and causing injury to the cable po- Itwill be observed that when convolutions of the conduit whereupon dirt and grit is prevented from entering the conduit.

While preferred embodiments of the invention have been described, it is to be understood that these are given merely as examples of the underlying principles of the invention and since these may be incorporated in other specific mechanical structures, I do not intend to be limited to those shown, except as such limitations are clearly imposed by the appended claims.

Having thus described the various features of the invention, what I claim is new and desire to secure by Letters Patent is:

July 21, 1936. R, 5 SANFORD 2,048,472

BRAKE Filed April 25, 1951 v 2 Sheets-Sheet 1 III I N V EN TOR. For 5 5,4NFOAD A TTORNE Y. 

